Electrical vacuum device



Aug. 9, 1932. D. s. GUSTIN ELECTRICAL VACUUM DEVICE Filed June 5, 1928 INVENTOR D. S. qus'rm BY ATTORN Patented Aug. 9, 1932 UNITED STATES PATENT OFFICE-.11

DANIEL SNYDER GUSTIN, 0F BLOOMFIELD, NEW JERSEY, ASSIGNOR '10 WESTINGHOUSE LAMP COMPANY, A CORPORATION OF PENNSYLVANIA ELECTRICAL VACUUM DEVICE Application filed June 5, 1928. Serial in. 282,989.

This invention relates to the manufacture of electrical vacuum devices and more particularly to incandescent electric lamps.

An incandescent electric lamp as commonly manufactured includes a bulb in which is sealed :1 mount, constituting the internal structure of the lamp. The bulb is then evacuated and tipped off and a base, usually in the form of a metallic screw cap, is secured to the neck of the bulb, the cap having a central contact for one of the leading-in wires extending from the mount While the opposite leading-in wire is usually secured to the side of the base.

A lamp mount as heretofore produced for the so-called tipless type of lamp included an exhaust tube, a flare tube and an arbor. These three elements, which were constructed of glass, were suitably positioned with leading-in conductors extending through the flare tube while sufficient heat was applied to certain portions of the assembled parts to render them plastic, after which the plastic portion was compressed in what was termed a press, in which the leading-in conductors were sealed. While the glass was still in a softened state, a current of air was directed through the exhaust tube to produce an aperture adjacent to the pressed portion ofthe consolidated parts. These consolidated parts constituted a stem, one end of which terminated in the glass rod or arbor. Support wires were then inserted radially and in spaced relation about the free end of the arbor and a filament was mounted in the support wires, the ends of the filament being secured to ends of leading-in wires. The stem having the filament secured thereto was termed the mount and the mount was then sealed to the neck of the bulb, after which an exhausting operation was performed to evacuate the bulb and then the exhausted tube was tipped ofl', sealing the bulb from the atmosphere.

From the foregoing it will be evident that an incandescent electric lamp as at present constructed embodies a multiplicity of parts and requires a plurality of operations. Fur-- thermore, inasmuch as an incandescent electric lamp must necessarily be made at high speed and in large volume and manufactured at a mimmum cost, it is essential to econo- Inize not only in operations and in the number of parts but also in the amount of material employed for'the respective parts or elements of the device.

It is an object of the present invention, therefore, to provide an incandescent electric lamp of simple construction and with a minimum amount of material.

Another object of the invention is to provide an incandescent electric lamp which may be manufactured at a relatively highrate of speed and with a minimum amount of manual labor.

Other objects and advantages of the invention will be more fully understood from the following description and accompanying drawing, in which Figure 1 shows an assembly of the component parts of a lamp constructed in accord ance with the present invention;

Figure 2 is a View of the lamp constructed in accordance with the present invention and having a base applied thereto;

Figure 3 is a transverse cross sectional view taken on line IIIIII in Figure 2, portions of support Wires being shown in full lines;

Figure 4 is a plan View of the filament and supports taken substantially on line IV-IV in Figure 2; and a Figure 5 is an enlarged fragmentary sectional view of a lamp with a modified form of exhaust tube.

A lamp constructed in accordance with the present invention may comprise a bulb 10 which is positioned with the neck 11 thereof disposed about a flange 12 having an annulus 12, thus forming a cup shaped portion 13" position of leading-in wires 14 and 15 and a support wire 16 between the annulus of the cup shaped portion and the interior surface of the neck 11, the leading-in wires and a sup port wire being tied together by a bead 17 of glass or other non-conductive material. A

filament 18 which may be of coil type is mounted upon the upper ends of the leadingin wires and the support wire, the ends of the filament being clam ed at 19 and 20 to the leadin -in wires an securedin a loop 21 at the en of the support wire, or if desirable the support wire may also be clamped to the filament. The bulb is then sealed to the annulus of the exhaust tube by heating through suitable fires 22 and the exhaust tube is inserted into an exhaust port 23 of an exhaust machine not shown). After the bulb isexhausted,

res 24 may be directed upon the exhaust tube adjacent to the cup shaped portionto perform a tipping-off operation which results in tip 25, thereby sealing the bulb from the atmosphere. A base 26 may then be applled to the end of the bulb and secured to the same by a suitable cement 27 in the usual manner. Leading-in wire 14 having been connected at .28 to a central contact 29 of the base while the leading-in wire 15 may be connected at 30 A to the side of the base.

It will be understood that the above brief description of operations is general and that in practice the usual sealing-in and exhuast machines may be used which are provided with suitable heads or holders for the several parts to be united.

From theforegoing it will be evident that whereas a mount as heretofore constructed included several glass parts, namely, the arbor, flare tube and-exhaust tube, the present invention makes it possible to produce a mount of metallic members secured together by a non-conductive element as the bead 17. This s t pe of mount lends itself to high speed prouction since the lead wires 14: and 15 and the a support wire 16 may be fed from spools and the ends thereof readily clamped to a filament. The glass bead may then be applied to the wires at the proper distance from the seal so as to bond the wires in a definite spaced relation. The wires may then be severed to the proper length, the result being a complete mount of simple and eifective construction and free from any glass supports. The ends of the leading-in wires and the support wire which embrace the cup shaped portion of the exhaust tube, may readily be shaped to proper form so that the mount may be dlsposed in po- I sition and the bulb disposed with its neck pacts during transportation or handling in general.

Another advantage of the present construction lies in the rapidity with which the bulb may be evacuated. It is well known that the rate of evacuation of an incandescent electric lamp is largel determined not only by the area of the out et port of the exhaust tube but by the combined areas of the surfaces over which the gases must pass during exhaust. In the resent construction the'exhaust tube may e of relatively large'cross' sectional area so that the gases have free passage to the pumps while the length of the passage as determined by the exhaust tube itselfis relatively short compared to the passage of lamps employing an exhaust tube which extends up into the bulb and has its outlet at the press portion thereof. Furthermore, by reason of the present form of exhaust tube the diameter of the passage therein may be relatively large since such diameter is limited only by the neck of the bulb, where as in the usual type of lam the diameter of the exhaust tube is limited y the flare tube. It is appreciated that the exhaust tube cannot be of too great a diameter since it is necessary for the wall to collapse, but with the present construction the maximum diameter for exhaust may be attained.

With the present construction, therefore, an incandescent electric lamp may not only be manufactured at a relatively low cost by reason of the economy of material and operation, but only a minimum amount of time need be consumed in the operation of exhausting, which is an important factor in an article of the present character.

The present idea includes the use of. an exhaust tube having an enlarged or flanged. end, the flanged end being cup shaped to provide an annulus 12 forunion with the neck of a bulb. An annulus 12", however, may be provided as shown in Figure 5 on the normal lower side of the flange 12. This construction makes it more convenient to erform the sealing-in operation in that the res may more readily sever the cullet or excess neck portion 31 of the bulb.

Although a preferred embodiment of the invention is shown and described herein, it is to be'understood that modifications may be made therein without departing from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

1. An incandescent electric lamp comprising a bulb, an exhaust tube terminating in an enlarged annular flange fused to the neck of said bulb, a mount including a plurality of support members held in spaced relation by a non-conductive member, a filament mounted on the ends of said support members, the opposite ends of said members extending through the neck'of said bulb and disposed in spaced relation to provide a three point support for said filament.

2. An incandescent lamp comprising a bulb, a mount including a'plurality of support members, means for holding said members in spaced relation, a filament mounted at the upper ends of said support members, a closure for the neck of said bulb comprising an exhaust tube terminating in a flanged portion, said support members being bent outwardly and sealed between said closure and the edge of the bulb neck to provide a multiple point support for said filament.

3. An incandescent electric lamp comprising a bulb, support wires within said bulb, a filament mounted on the free ends of said support wires, an exhaust tube terminating in a flange of slightly less outside diameter than the inside diameter of the neck of said bulb, said support wires extending between said flange and said bulbneck for consolidating therewith when said bulb and flange are fused together.

4. An electrical device comprising a bulb, an exhaust tube terminating in a flanged portion to fit the neck of said bulb, support wires, a filament mounted at the free ends of said support wires and disposed on the longitudinal axis of said bulb, the opposite ends of said support wires extending outwardly from said axial line and between said flange and bulb neck to provide a multi-point support for said filament.

5. An electrical device comprising a bulb, a flanged cup shaped closure for said bulb neck, an exhaust tube extending from the base of said cup to provide a communicating passage to the interior of said bulb when said bulb neck is consolidated with said neck and filament support members sealed between said flange and said bulb neck. I

In testimony whereof, I have hereunto subscribed my name this 4th day of June, 1928.

DANIEL SNYDER GUSTIN. 

